The Postal Service collects the fee on each package bearing CBP Form 3419ALT. When a single mail entry form covers several packages, the Postal Service collects the fee only on the package bearing CBP Form 3419ALT. The CBP Form 3419ALT is enclosed in an orange adhesive-backed Treasury Department envelope attached to the outside wrapper or envelope. The form indicates the tariff item number, rate of duty, and amount of duty to be collected plus a customs processing fee, which is assessed on all dutiable mail shipments.